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There's a hard physical limit (the Rayleigh criterion) on the resolution of an optical system by how big the open end is. You won't get "super zoom" capabilities without a satellite the size of a stadium. https://en.wikipedia.org/wiki/KH-11_KENNEN#Resolution_and_gr...



What about multiple satellites working to get one image?

Like the arrays we have on Earth pointing to space, but instead, arrays on space pointing to Earth.

I know there probably isn't that many KH-style satellites to do it, but would it be possible?


The alignment has to be better than half a wavelength. That's doable for RF, but for optical telescopes you're talking nanometers. That's not possible (currently or in the foreseeable future) for a spacecraft constellation.


Amusingly enough, there's been some groundwork laid here by gravity wave interferometer constellations: https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...

You could imagine a deep-infrared mission (longer wavelength, to soften the alignment requirements) launched into deep space (Jupiter+) where both the solar wind density is lower (reducing space weather perturbations) and reduced solar flux would reduce heat loads on the structure, (objects in Jupiter orbit get 3.6% as much light as in Earth orbits) making cooling easier. An interferometer design would also improve resolution. A not-widely advertised feature of the JWST is that, due to the same Rayleigh limits, its far infrared modes have dramatically lower resolution than its near infrared camera. A problem with a 6 meter mirror, less of a problem with a kilometer mirror.


I remembered European Southern Observatory employing optical interferometry on the ground. And indeed it does: https://www.eso.org/public/news/eso1905/


Cool to see Clifford Stoll mentioned there, he was also the one detecting one of the first international state-sponsored hacking attacks on the US and wrote a book about it, The Cuckoo's Egg.




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